Simpson compound planetary gears

Green - Front ring gear (not attached to a shaft)

Yellow - Both sun gears (mounted on an outer shaft)

Red - Rear carrier (not attached to a shaft)

Blue - Front carrier and rear ring gear. (attached to the output shaft)

Purple - Front and rear planet gears

1st - Hold the red and turn the green. Blue is 40% of input

2nd - Hold the yellow and turn the green. Blue is 66% of input

3rd - Turn the green and yellow. Blue is 100% of input

Overdrive - Hold the yellow and turn the red. Blue is 150% of input

Reverse - Hold the red and turn the yellow. Blue is 50% of input backwards